DUE TO DEATH
Regina Extra w/ 3RB-1 Body 13-14-15-16-17 RARE NOS
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This freewheel is rare in that the 'corncob' or 'straight block'Regina 5-speed with a 13 tooth cog is only possible with a special body, dubbed '3RB-1' by Regina. The difference is that only one cog threads from the back of the freewheel instead of the usual two. The size, or diameter, of this inner plateau (cogs that fit here are called 'Position 3') meant that a 17 tooth cog was the smallest position 3 cog possible. Thus, a straight block from a '14' would have a 3-17 and a 3-18 as the two inner cogs. This special body was Regina's answer to the increasing use of the 13 tooth outer cog by professional racers, who were now demanding straight blocks from a 13 tooth outer cog.
The second photo contrasts the 'normal' body used on Corsa, Extra, and Oro models(right) with the 3RB-1 body(left). Note the two inner cogs(a 3-18 and a 3-20) have their shoulders facing eacr other on the right hand freewheel while the single position 3 cog on the left has its shoulder facing to the back of the freewheel.
The third photo shows the freewheel with four of the cogs removed. The tool the freewheel is resting on is called a 'last cog removing tool'.
click on a picture to enlarge